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Facile low-temperature supercritical carbonization method to prepare high-loading nickel single atom catalysts for efficient photodegradation of tetracycline

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Journal of Environmental Sciences 2024年第4期138卷 373-384页

作者： Han Qiao Lirong Zheng Shiwen Hu Gang Tang Hongri Suo Chongxuan Liu School of Environment Harbin Institute of TechnologyHarbin 150090China State Environmental Protection Key Laboratory of Integrated Surface Water-groundwater Pollution Control School of Environmental Science and EngineeringSouthern University of Science and TechnologyShenzhen 518055China Beijing Synchrotron Radiation Facility(BSRF) Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China

Environmental photocatalysis is a promising technology for treating antibiotics in wastewater.In this study,a supercritical carbonization method was developed to synthesize a single-atom photocatalyst with a high loading of Ni(above 5 wt.%)anchored on a carbonnitrogen-silicate substrate for the efficient photodegradation of a ubiquitous environmental contaminant of tetracycline(TC).The photocatalyst was prepared from an easily obtained metal-biopolymer-inorganic supramolecular hydrogel,followed by supercritical drying and carbonization treatment.The low-temperature(300℃)supercritical ethanol treatment prevents the excessive structural degradation of hydrogel and greatly reduces the metal clustering and aggregation,which contributed to the high Ni loading.Atomic characterizations confirmed that Ni was present at isolated sites and stabilized by Ni-N and Ni-O bonds in a Ni-(N/O)_(6)-C/SiC configuration.A 5%Ni-C-Si catalyst,which performed the best among the studied catalysts,exhibited a wide visible light response with a narrow bandgap of 1.45 eV that could efficiently and repeatedly catalyze the oxidation of TC with a conversion rate of almost 100% within 40 min.The reactive species trapping experiments and electron spin resonance(ESR)tests demonstrated that the h+,and·O_(2)-were mainly responsible for TC degradation.The TC degradation mechanism and possible reaction pathways were provided also.Overall,this study proposed a novel strategy to synthesize a high metal loading singleatom photocatalyst that can efficiently remove TC with high concentrations,and this strategy might be extended for synthesis of other carbon-based single-atom catalysts with valuable properties.

关键词： Carbon-based single-atom catalyst Nickel Photocatalytic degradation Tetracycline Visible light

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Robust reinforcement learning with UUB guarantee for safe motion control of autonomous robots

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Science China(Technological Sciences) 2024年第1期67卷 172-182页

作者： ZHANG RuiXian HAN YiNing SU Man LIN ZeFeng LI HaoWei ZHANG LiXian School of Astronautics Harbin Institute of TechnologyHarbin 150001China School of management Harbin Institute of TechnologyHarbin 150001China Beijing institute of Tracking and Telecommunication Technology Beijing 100094China

This paper addresses the issue of safety in reinforcement learning(RL)with disturbances and its application in the safety-constrained motion control of autonomous robots.To tackle this problem,a robust Lyapunov value function(rLVF)is proposed.The rLVF is obtained by introducing a data-based LVF under the worst-case disturbance of the observed state.Using the rLVF,a uniformly ultimate boundedness criterion is established.This criterion is desired to ensure that the cost function,which serves as a safety criterion,ultimately converges to a range via the policy to be designed.Moreover,to mitigate the drastic variation of the rLVF caused by differences in states,a smoothing regularization of the rLVF is introduced.To train policies with safety guarantees under the worst disturbances of the observed states,an off-policy robust RL algorithm is proposed.The proposed algorithm is applied to motion control tasks of an autonomous vehicle and a cartpole,which involve external disturbances and variations of the model parameters,respectively.The experimental results demonstrate the effectiveness of the theoretical findings and the advantages of the proposed algorithm in terms of robustness and safety.

关键词： motion control reinforcement learning robustness stability

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Hydrochemical Characterization,Controlling Factors and Water Quality of Surface Water in Shandong Province,North China

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Journal of Earth Science 2024年第1期35卷 155-166页

作者： Ran An Jiutan Liu Zongjun Gao Changsuo Li Yuming Peng School of Earth Sciences and Resources China University of GeosciencesBeijing 100083China College of Earth Science and Engineering Shandong University of Science and TechnologyQingdao 266590China 801 institute of Hydrogeology and Engineering Geology Shandong Provincial Bureau of Geology&Mineral ResourcesJinan 250014China Key Laboratory of groundwater Resources and Environment Shandong Provincial Bureau of Geology&Mineral ResourcesJinan 250014China Shandong Engineering Research Center for groundwater Environmental Protection and Remediation Jinan 250014China

In this study,90 surface water samples were collected from Shandong Province(SDP)in the dry and wet seasons and analyzed using statistical analysis,hydrochemical methods and water quality index(WQI).The content of main ions showed seasonal variations,with a higher average value in the dry season than in the wet season.Sampling points exhibiting high contents of the main chemical components were mainly distributed in areas southwest of SDP,north of Weifang,and around Jinan.The saturation index of carbonate minerals was greater than zero,while that of evaporite minerals was less than zero.The hydrochemical characteristics of surface water are mainly dominated by rock weathering as well as cation exchange.In addition,surface water in SDP has significantly been affected by anthropogenic factors.Most of the surface water could be classified as weakly alkaline soft-fresh water,with the hydrochemical types of SO_(4)·Cl-Ca·Mg and SO_(4)·Cl-Na.In terms of WQI,47.88% and 37.88% of the water samples in SDP were classified as poor water in the dry and wet seasons,respectively.On the whole,the water quality is higher in the wet season than in the dry season,and surface water in SDP is generally suitable for agricultural irrigation.

关键词： surface water hydrochemical characteristics controlling factors water quality Shandong Province

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Rodent biology and ecologically based rodent management(EBRM)-25 years of progress through promoting multidisciplinary research

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Integrative Zoology 2024年第1期19卷 2-7页

作者： Grant R. SINGLETON Lyn A. HINDS Rhodes MAKUNDI Steven R. BELMAIN Natural Resources institute University of Greenwich Kent UK CSIRO Health and Biosecurity Canberra ACT Australia African Centre of Excellence for Innovative Rodent Pest management and Biosensor Technology Development Sokoine University of Agriculture Morogoro Tanzania institute of Pest management Sokoine University of Agriculture Morogoro Tanzania

“During rodent outbreak years in eastern Africa,lo-cally,more than 80%of the potential harvest may be lost,but even in non-outbreak periods,rodents cause chronic damage to crops….The pest rodent story in Africa in-volves several species embedded in a broad and variable landscape with highly variable densities.”(Leirs et al.2010).

关键词： damage crops

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Multiple isotopes reveal the driving mechanism of high NO_(3)^(-) level and key processes of nitrogen cycling in the lower reaches of Yellow River

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Journal of Environmental Sciences 2024年第4期138卷 597-606页

作者： Qianqian Zhang Huiwei Wang Lu Liu Tianlun Zhai Xueqing Zhang Hebei and China Geological Survey Key Laboratory of groundwater Remediation Institute of Hydrogeology and Environmental GeologyChinese Academy of Geological SciencesHebei 050061China Geo-Environmental Monitoring institute of Hebei Province Hebei 050011China Hebei Provincial Laboratory of Water Environmental Science Hebei 050037China Hebei Provincial Academy of Ecological Environmental Science Hebei 050037China

The continuous increase of nitrate(NO_(3)^(-))level in rivers is a hot issue in the world.However,the driving mechanism of high NO_(3)^(-)level in large rivers is still lacking,which has limited the use of river water and increased the cost of water treatment.In this study,multiple isotopes and source resolution models are applied to identify the driving mechanism of high NO_(3)^(-)level and key processes of nitrogen cycling in the lower reaches of the Yellow River(LRYR).The major sources of NO_(3)^(-)were sewage and manure(SAM)in the low-flow season and soil nitrogen(SN)and chemical fertilizer(CF)in the high-flow season.Nitrification was the most key process of nitrogen cycling in the LRYR.However,in the biological removal processes,denitrification may not occur significantly.The temporal variation of contributions of NO_(3)^(-)sources were estimated by a source resolution model in the LRYR.The proportional contributions of SAM and CF to NO_(3)^(-)in the low-flow and high-flow season were 32.5%-52.3%,44.2%-46.2%and 36.0%-40.8%,54.9%-56.9%,respectively.The driving mechanisms of high NO_(3)^(-)level were unreasonable sewage discharge,intensity rainfall runoff,nitrification and lack of nitrate removal capacity.To control the NO_(3)^(-)concentration,targeted measures should be implemented to improve the capacity of sewage and wastewater treatment,increase the utilization efficiency of nitrogen fertilizer and construct ecological engineering.This study deepens the understanding of the driving mechanism of high nitrate level and provides a vital reference for nitrogen pollution control in rivers to other area of the world.

关键词： Nitrate Driving mechanism Nitrogen cycle Source apportionment Transformation Yellow River

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Community-Level Practice Checklists for Health Protection During Cold Spells in China

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China CDC weekly 2024年第5期6卷 83-87页

作者： Jing Shang Mengzhen Zhao Zhao Liu Xiya Zhang Shiguang Miao Ishaq D.Sulaymon Wenjia Cai institute of Urban Meteorology CMABeijingChina School of management and Economics Beijing Institute of TechnologyBeijingChina School of Airport Economics and management Beijing Institute of Economics and ManagementBeijingChina Department of Earth System Science Tsinghua UniversityBeijingChina Sand and Dust Storm Warning Regional Center National Center for MeteorologyJeddahSaudi Arabia Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control Collaborative Innovation Center of Atmospheric Environment and Equipment TechnologySchool of Environmental Science and EngineeringNanjing University of Information Science and TechnologyNanjing CityJiangsu ProvinceChina

Communities play a crucial role in protecting the health of vulnerable populations such as the elderly,low-income groups,and high-risk individuals during cold spells.However,current strategies for responding to cold spells primarily consist of programmatic policies that lack practicality,specificity,and detailed implementation guidelines for community workers.Therefore,this study aims to identify and analyze the challenges faced by communities in responding to cold spells,review international experiences,and develop a set of practical checklists for community-level health protection.These checklists will assist community workers and volunteers in effectively preparing for,responding to,and recovering from cold spells.

关键词： preparing income primarily

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Model of fractured medium and nondestructive control of composite materials

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Chinese Journal of Aeronautics 2024年第2期37卷 93-99页

作者： Vasily GOLUBEV Ilia NIKITIN Katerina BEKLEMYSHEVA Department of Computers Science and Numerical Mathematics Moscow Institute of Physics and TechnologyDolgoprudny 141700Russia Mathematical Modeling and management Department of InformatizationInstitute of Computer Aided Design RASMoscow 123056Russia

Non-destructive testing of composites is an important issue in the modern aircraft industry.Composites are susceptible to the barely visible impact damage which can affect the residual strength of the material and occurs both during production and operation.The continuum model for describing the damaged zone is presented.The slip theory relations used for a continuous distribution of slip planes are applied.At the initial stage,the isotropic background model is used.This model allows the material slippage along the fractures based on the Coulomb friction law with the small viscous addition.In this regime,the govern system of equations becomes rigid.To overcome this difficulty,the explicit-implicit grid-characteristic scheme is proposed.The standard ultrasound diagnostic procedure of damaged composite materials is successfully simulated.Compared with the trivial free-surface fracture model,different reactions on the compression and stretch waves are registered.This approach provided an effective way for the simulation of complex dynamic behavior of damage zones.

关键词： Non-destructive testing Composite materials Numerical modeling Continuum model Grid-characteristic method

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Digital technology,the industrial internet,and cost stickiness

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China Journal of Accounting Research 2024年第1期17卷 45-73页

作者： Lili Hui Huobao Xie Xiaofang Chen School of management Wuhan University of TechnologyWuhanChina Research institute of Digital Governance and management Decision Innovation Wuhan University of TechnologyWuhanChina School of Economics and management Wuhan UniversityWuhanChina

The deep integration of digital technology with the real economy has reconstructed production systems.We explore the impact of digital technology on the resource allocation behavior and efficiency of manufacturing enterprises.Using a sample of Chinese A-share listed manufacturing firms over the 2010–2021 period,we find that digital technology alleviates cost stickiness,especially in enterprises with a high level of Industrial Internet platform usage.This effect occurs by optimizing the labor force structure and improving the economic benefits of labor capital investment.Heterogeneity analysis shows that this effect is pronounced in enterprises with high levels of labor intensity and business complexity.Our findings shed new light on the consequences and mechanism of enterprise cost optimization that is driven by technologydriven reforms.

关键词： Digital Technology Cost Stickiness The Industrial Internet Labor Production Factor Empowerment

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Emission-side drivers affecting carbon neutrality based on vegetation carbon sequestration:Evidence from China

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Chinese Journal of Population,Resources and Environment 2024年第1期22卷 87-97页

作者： Han Wang Research institute of Economics and management Southwestern University of Finance and EconomicsChengdu 611130China

To address climate change,the world needs deep decarbonization to achieve carbon neutrality(CN),which implies net-zero human-caused CO_(2) emissions in the atmosphere.This study used emission-side drivers,including socioeconomic and net primary productivity(NPP)-based factors,to determine the changes in CN based on vegetation carbon sequestration in the case of China during 2001-2015.Spatial exploratory analysis as well as the combined use of production-theoretical decomposition analysis(PDA)and an econometric model were also utilized.We showed that CN was significantly spatially correlated over the study period;Yunnan,Heilongjiang,and Jilin presented positive spatial autocorrelations,whereas Guizhou showed a negative spatial autocorrelation.More than half of CN declined over the period during which potential energy intensity(PEIE)and energy usage technological change were the largest negative and positive drivers for increasing CN.PEIE played a significantly negative role in increasing CN.We advise policymakers to focus more on emission-side drivers(e.g.,energy intensity)in addition to strengthening NPP management to achieve CN.

关键词： Carbon neutrality Vegetation carbon sequestration Production-theoretical decomposition analysis Econometric model

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基于文献回顾的有色金属冶炼废渣的特征、资源化途径及其安全利用评价

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Journal of Central South University 2024年第4期31卷 1178-1196页

作者：徐则林姚佳斌付融冰 Centre for Environmental Risk management and Remediation of Soil and groundwater Tongji UniversityShanghai 200092China State Key Laboratory of Pollution Control and Resource Reuse College of Environmental Science and EngineeringTongji UniversityShanghai 200092China Shanghai institute of Pollution Control and Ecological Security Shanghai 200092China

冶炼废渣作为冶炼过程中产生的工业副产物,由于其缺乏安全、合理的防护和管理措施可能导致环境问题。通过全面分析近年来发表的相关文献,本文对有色金属冶炼废渣的特性、资源化利用途径及安全利用评价等方面的最新研究进展进行了介绍。... 详细信息

冶炼废渣作为冶炼过程中产生的工业副产物,由于其缺乏安全、合理的防护和管理措施可能导致环境问题。通过全面分析近年来发表的相关文献,本文对有色金属冶炼废渣的特性、资源化利用途径及安全利用评价等方面的最新研究进展进行了介绍。研究结果表明,不同的原生精矿、冶炼条件和冶炼类型决定了冶炼废渣的化学和矿物学特征。此外,冶炼废渣在各种资源化利用中表现出极高的灵活性,不仅可以用于金属回收和建筑材料,还可以作为农业肥料和修复剂。同时,本文强调了在各种利用情景下对废渣进行安全性评估的重要性,以降低其潜在环境风险。此外,本文还强调了未来的研究方向,包括建立一种综合且量化的土渣混合体中重金属环境风险评价方法,以及探索更多创新的冶炼废渣资源化利用方法。综上所述,本文对于推动冶炼废渣在环境保护和资源可持续利用方面的研究有重要意义。

关键词：冶炼废渣有色金属废渣特征资源化利用途径安全利用评价

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